Step 3: Determine cup size
Subtract your band size (step 1) from your bust size (step 2). This number equates to the letter of your cup size. With our model we would subtract 34 from 37, which is 3 inches. According to the chart, she would wear a 34C.
Media personality and fashion expert Stephenie Wise, who has a style segment on WISH-TV's Indy Style, provided these tips to determine proper bra size.